Quoted from Quench:
Unfortunately clear details on this are not listed in the schematics :-/
Any chance you or someone else can comment on what the wire colors are at the solenoid driver board connector J2 pin 15 (left bottom most wire), and also the wire color at the rectifier board in the cabinet at J3 pin 13?
OK.
Here is the short answer:
1) Rectifier J3-13 is a dark blue/white wire that travels to the flipper coil on the displays board. From the coil, the Blu/W wire and now also a Black wire travel up to the relay. (Dark Blue/W can also be Light Blue/ White wire instead).
2) From the right hand flipper (see more below about the confusion below) a Red/Yellow pairs up with the Blu/W wire at the rectifier board and travels to the relay. These two wires are joined into a connector (this is the connector the questioner cannot find the female on his Catacomb.)
2) At the relay, a Red/White wire travels to SDU J2-15.
That's it. That is your circuit.
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Pin J3-13 is a dark blue wire with white stripe. See yellow tie wrap at the connector. While I did not do a continuity check, I am reasonably certain this Blu-W wire travels to the flipper coil on the displays/bagatelle board. From the coil this Blu/W wire travels up to the relay. There is also a black wire that travels from the coil to the relay.
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The relay has 4 wires attached. The four wire colors are:
1) The familiar Dark Blue/White wire from the flipper coil is located to the left side of the relay to the rear.
2) The black wire located at the flipper coil is located to the right side of the relay.
IMG_2514 (resized).JPG
2) A Red/white wire is positioned in front of dark blue wire. There is a diode between these two wires; The banded side of the diode faces the dark blue wire. This R/W wire travels to SDU J2-15. This has been verified with a continuity check.
3) There is also a red/yellow wire at the relay.
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The dark blue/white wire and red/yellow wire pair off and travels across the displays board to a 2-pin connector that I am holding between thumb and forefinger.
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The other side of the 2-pin connector carries the same Blu/W wire and Red/Y wire into the play field harness. Traveling down this harness, the Blu/W wire terminates at J3-13 on the rectifier board where we started out at.
IMG_2512 (resized).JPG
While the Blu/W wire terminates at J3-13, the Red/Y wire connects to a red wire that travels to the right flipper. This is as far as I can trace the Red/Y wire. I am going to have to cut some tie wraps so I can see what this action is because I see a Red/Y wire on the left flipper, as well.
IMG_2515 (resized).JPG